Blocks in C Language
A block is a set of zeor or more statements enclosed in braces. Blocks are also known as compound statements. Often, a block is used as the body of an if statement or a loop statement, to group statements together.
for(x = 1; x <= 10; x++) {
printf("x is %d\n", x);
if((x % 2) == 0)
printf("%d is even\n", x);
else
printf("%d is odd\n", x);
}
You can also put blocks inside other blocks:
for(x = 1; x <= 10; x++) {
if((x % 2) == 0) {
printf("x is %d\n", x);
printf("%d is even\n", x);
} else {
printf("x is %d\n", x);
printf("%d is odd\n", x);
}
}
You can declare variables inside a block; such variables are local to that block. In C89, declarations must occur before other statements, and so sometimes it is useful to introduce a block simply for this purpose:
{
int x = 5;
printf("%d\n", x);
}
printf("%d\n", x); /* Compilation error! x exists only in the preceding block. */